As a certified vibration specialist I would agree vibrations get worse with speed. It’s not hard or a lot of cost to change a balancer, just not sold it’s your issue. So change it and see what happens
Bad harmonic balancer symptoms?
- Thread starter Clone TIE Pilot
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I am not sure how long it could have been slipped. I have the base timing at 12 degrees BTDC with a hot ZZ4 chip, and the engine seems to want more advance, could be a sign of retarded timing marks?
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Years ago I had one slip on a SBC and it ran best way too advanced but then when I checked the balancers relationship between the keyway and the zero mark I realized it had moved but it still ran the same
I would assume the longer one continues to run a slipped damper, the further it will continue to slip out of postion and progressively become worse. The outer rings can also shift inboard and even crooked to the hub which probably would really throw the damper's tune off. If the rubber turned hard in the damper, which I suspect in my case, it can no longer asborb the harmonics.
The idea of the damper is that the outer ring and rubber insert absorb the harmonics and radiate them out as heat. With OEM dampers its a solid rubber ring pressed in between the hub and outer iron ring. So its just friction keeping the rings in proper position. The aftermarket replacement dampers use injected rubber instead so there is a bond between the rubber, hub, and outer ring which is better than stock.
I do have a squeal from the belt drives which could be the damper.
Already have a used Kent Moore harmonic balancer installer tool I got a couple of years ago for cheap.
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Two suggestions,
Motor mounts can cause the same feeling. Does it change when placed in drive or reverse.
This next one i doubt you did but will throw it out for public info.
Check your oil level, i have seen over filled crankcases do this. And when i say overfilled, i mean, some one thought they drained the oil but didnt. Then they added the 5 quarts oil. 10 quarts of oil in a 5 quart system will cause a feeling of misfire.
Motor mounts can cause the same feeling. Does it change when placed in drive or reverse.
This next one i doubt you did but will throw it out for public info.
Check your oil level, i have seen over filled crankcases do this. And when i say overfilled, i mean, some one thought they drained the oil but didnt. Then they added the 5 quarts oil. 10 quarts of oil in a 5 quart system will cause a feeling of misfire.
I think it would be more likely that someone would drain the oil and install a new filter with oil but forget to fill the crankcase than thinking you drained the oil and adding 5 more quarts and then not checking the oil level.
And yes I know there are plenty of idiots out there.
Think express lube service. Like jiffy lube or a dealership where you have multiple people under the car draining oil on multiple vehicles and multiple people on top filling. I've seen it happen. Then the oil changers move the car, but don't notice the problem cause it didn't run long enough and there is no oil light on. Then the customer comes back with a rough running complaint but never mentions it started after the oil change. Communication and situational awareness are under rated skills.
Yes, i agree, there are plenty of idiots out there.
Yeah, that makes sense I have never been to an oil change place or a dealer and have always changed my own oil in all my cars since I was a teenager.
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